Sofa



FIG. 1 is a front perspective view of a sofa showing our new design;

FIG. 2 is a rear perspective view;

FIG. 3 is a right side elevational view;

FIG. 4 is a front perspective view of a sofa showing a second embodiment of our new design;

FIG. 5 is a rear perspective view of FIG. 4; and,

FIG. 6 is a right side elevational view of FIG. 4. 

The ornamental design for a sofa, as shown and described. 